To damp as quickly as possible the lateral (horizontal) vibration of a structure such as a building for businesses or offices, a multiple dwelling house, and a detached house, which serve as buildings, as well as a bridge, an abutment, and the like due to an earthquake, winds, traffic vibrations, and the like, vibration dampers such as lead dampers, viscous dampers, steel rod dampers, and the like are used. However, since such vibration dampers are, in many cases, disposed between the structure and the ground, the vibration dampers have a problem in that they are difficult to be applied to existing structures.
On the other hand, so-called vibration isolating walls in which damper such as those described above are installed in walls of the structure can be easily applied to an existing structure. However, with such vibration isolating walls, regardless of whether the structure is newly constructed or is an existing one, in a case where a necessary number of walls for obtaining the vibration damping effect in application are not present, there arises a need to install new walls within the structure to partition the interior of the structure into small units. In addition, in places which are to be used as passages for connecting together rooms of the structure, the new walls cannot be installed. In this respect, the degree of freedom of installation is restricted.
In addition, in the case of a vibration damper in which a resistance plate is disposed in a box member, a viscous material is filled in the gap between the box member and the resistance plate, and the viscous material is adapted to be sheared by the relative displacement of the resistance plate with respect to the box member so as to absorb the relative displacement energy by the shearing of the viscous material, large angular moment occurs in the box member and the resistance plate in the relative displacement. Hence, there is a need to firmly connect the box member and the resistance plate to the structure so as to be able to withstand this large angular moment.
Generally, since the connecting structure is arranged such that the box member and the resistance plate are connected to the structure by using a multiplicity of bolts and steel plates having substantial thickness, a large space is occupied by this connecting structure. Hence, the space for installing the box member and the resistance plate is substantially restricted, and the size of the rooms of the structure is limited. In particular, since tensile and compressive forces based on the bending moment are particularly concentrated on lateral end portions of the box member and the resistance plate, unless their strength is sufficient, there is the possibility of occurrence of localized buckling there. From the viewpoint of preventing this localized buckling as well, the connecting structure becomes large, and the space for installing the box member and the resistance plate which demonstrate the damping performance becomes limited. In addition, since the area of the resistance plate becomes small, the capability of the vibration damper declines, and there is a possibility that the rooms of the structure are made small due to the jutting out of the large connecting structure in antiplane directions.
The present invention has been devised in view of the above-described aspects, and its object is to provide a vibration-damped structure which has sufficient withstanding force with a connecting structure whose occupying space is small without needing to partition the interior of the structure into small units and without being restricted by the passage space regardless of whether the structure is newly constructed or is an existing one, and which is capable of damping as quickly as possible the lateral deformation and vibration of columns due to an earthquake, winds, traffic vibrations, and the like, to thereby damp the vibration of the structure.